The Pons Aelius, much altered by Bernini in the 17c.
We are next to Hadrian's Mausoleum, looking across to the left bank of the Tiber.

Pons Aelius:
the modern Ponte S. Angelo, built by Hadrian in connection with
his mausoleum
(cf.Ill. 34) and finished in 134 A.D. (Cass. Diop397LXIX.23; CILVI.973;
Not. app.;
Pol. Silv. 545). It is represented on a bronze medallion of Hadrian which is accepted as genuine by Gnecchi (Med. II.42.4). Besides this official name the bridge was called pons Hadriani (Hist. Aug. Hadr. 19;
Prud. Peristeph. XII.61; Mirab. 11;
Pol. Silv. 545;
Ordo Bened. pass.), and in the Middle Ages Pons S. Petri (Anon. Magl. 158; Eins. pass.; Jord. I.1.416). It had three main arches 18.39 metres in diameter, with three smaller arches on the left, 3, 3.5 and 7.59 metres in diameter respectively, and two on the right, 7.59 and 3.75 in diameter. From the central part, over the main arches, the bridge sloped down at an angle of 15°, and the approach on the left side was by a long ramp. The total width was 10.95 metres, and the material travertine with peperino between the arches. The inscription (CILVI.973) was seen, probably on the parapet,1
in 1375 (Mitt. 1893, 321‑323), so that apparently this bridge suffered no great injury until December 1450, when the parapet was broken by the throngs of pilgrims, and restored by Nicholas V. In 1527 the statues of S. Peter and S. Paul were erected by Clement VII, and in 1669‑71 Clement IX placed on the parapet the famous statues representing angels (Mem. A.P. I.1.224). Two of the arches on the left side had become covered up, but the structure remained intact until the building of the present embankment in 1892 necessitated the reconstruction of the ends of the bridge, so that only the three central arches are now standing.

(For description and plans of the original bridge and an account of the changes and discoveries in 1892, see NS 1892, 231‑233; 412‑428; BC 1888, 129‑130; 1893, 14‑26; Mitt. 1893, 321‑323; LR 22‑24; JRS 1925, 75‑98.)

The Authors' Note:

1
Mr. S. R. Pierce informs me that he has noticed a few letters of a large inscription on the upstream side, in the archivolt moulding of the central arch. All that could be read was N(?). . .LI.

Thayer's Note: An even more observant Tyler Lansford writes me from Rome, Nov 08: "As I noticed just yesterday, this inscription is repeated on the downstream side of the bridge at the foot of the second pier from the north: N(icolaus) P(a)P(a) V MCCCCLI. It must refer to the restoration undertaken after the damage during the Jubilee of the year before. The downstream inscription is low enough to be covered by water when the river is high."

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